This invention relates to a hybridization assay utilizing nucleic acid probes labelled with lanthanide chelates that show time-delayed fluorescence.
Labelled nucleic acids have become indispensable in hybridization assays, performed both in vitro and, as in hybridocytochemical microscopy, also in vivo. Appropriate labelling of nucleic acids is a crucial point in their sequencing and applications may also be found in the different methodologies of nucleic acid separation. Nowadays, most of the efforts to find more sensitive markers have been made in the field of hybridization probes for the detection of specific, complementary nucleic acid sequences. This is natural in view of the great importance of such assays in medicine and molecular biology.
DNA or RNA can be labelled in a variety of ways. Generally, all labels may be detected directly i.e. the label, which is bonded to the nucleic acid is itself detectable, or indirectly when the label participates in one or more reactions thus generating detectable products.